For example, when an elderly person goes shopping and takes a walk, a walking assistance device such as a walking aid or a walker for an aged person has been known as an assistant tool for walking safely. Such a walking assistance device has front and rear legs provided with wheels, and includes a handle at the upper end portion of the main body frame. The user grabs the handle and travels the wheels with the physical body being supported, thereby attaining safe walking. Further, a walking assistance device has been developed which provides driving force to wheels by a motor or the like so as to apply brake on a downhill or the like or help going up on an uphill.
FIG. 22 is a side view showing a structure of a walking assistance device 800 described in Patent Document 1. Walking assistance device 800 supports the user by a supporting portion 801, and has a control device to control a motor 805 in accordance with respective outputs of a force sensor 802, a distance sensor 803, and a speed sensor as well as a parameter set by a setting device 804 so as to drive driving wheels 806, thereby controlling forward movement, backward movement, and turning movement of base body 807.
Specifically, walking assistance device 800 detects a distance between walking assistance device 800 and the user, and when the distance becomes larger than a predetermined distance, walking assistance device 800 controls the driving of walking assistance device 800, thereby securing a constant distance between the walking assistance device and the user to prevent the walker from leaning forward.
Accordingly, when the user is delayed in taking a step forward, the walking assistance device moves forward to provide a wide interval between the walking assistance device and the user so as to prevent the user from having a posture greatly leaning forward and to assist the user in readily returning to the previous posture.